Former Manchester United midfielder Paul Scholes has hailed the importance of Lisandro Martinez to the club.
Since arriving from Ajax in the summer, Martinez has started all six of United's Premier League games this season.
The 24-year-old has formed a solid defensive partnership alongside Raphael Varane, with the Red Devils conceding only two goals in the four games that the pair have played together.
However, there was concern when Martinez was forced off with 10 minutes remaining of Sunday's 3-1 win over Arsenal, and Scholes believes that the team could be weaker if the centre-back has a spell on the sidelines.
Commenting on Martinez after the game, Scholes told reporters: "At United it's about the determination more than anything.
"You know the talent is there but it's about getting up to people, stopping people, getting up to people, being solid at the back.
"Having that solid back four now is helping them. Martinez coming out of that might be a worry going forward."
United will be hoping that Martinez's injury is nothing serious as they look to claim a fifth consecutive victory in Thursday's Europa League encounter with Real Sociedad.
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